A canisterized missile is typically launched using the missile's own booster—so called “hot launch.” When the booster fires, a plume of high-temperature (i.e., in excess of 5000° F.), high-velocity exhaust gas is generated. Since the plume is quite erosive (e.g., due to its high velocity and sometimes the presence of metallic particulates, etc.), direct exposure to it adversely affects the missile, the missile canister, other launch structures, and the surrounding environs (e.g., deck of a ship, etc.).
As a consequence, most missile-launch systems include an exhaust-gas management system, which directs the booster plume away from the missile, launch structure, etc. But to survive the plume's extreme conditions, the launch structure, as well as the exhaust-gas management system itself, must incorporate thermal- and erosion-protection materials.
The exhaust-gas management system and thermal- and erosion-protection materials necessarily add weight, cost and complexity to the launching system. Furthermore, heating of the launch structure and deck that results from hot launch creates a residual thermal signature. This signature is readily detectable by various sensors, and therefore potentially compromises the survivability of the missile launcher and, indeed, the ship or vehicle that supports it.
To address the problems of hot launch, “cold launch” systems have been developed. In a cold launch, the missile's booster is not used to eject the missile from the missile canister; rather, some other means, which does not generate the high temperatures or the erosive flow of a missile plume, is used. After the missile clears the canister, the missile's booster fires, with minimal impact on the launch structure, etc.
Existing cold launch systems have a variety of drawbacks. One drawback is that most cold launch system include a substantial number of additional components. Another drawback is that in some cold launch systems, the missile is exposed to high-pressure gas from a gas generator (that provides the pressure for launch).